Hierarchical structure generating method and apparatus generating hierarchical structure display table based on parent-child relationship table

ABSTRACT

A hierarchical structure generating method and apparatus used in a communication system (for example, consisting of a parent station B and N child stations (relay station R or terminal station T) is disclosed, by which the whole hierarchical structure can be efficiently generated and displayed from the top level based on a parent-child relationship table between the constituent stations. The apparatus comprises a section for referring to a parent-child relationship table indicating each parent-child relationship between the elements, and generating and outputting a hierarchical structure display table which includes at least information for determining whether each element is a parent element; information for determining whether each parent element is a top parent element; information for determining a child element of each parent element; and information for determining another child element having the same hierarchical level of each child element, so as to analyze the hierarchical structure; and a section for generating and displaying the hierarchical structure of the elements by referring to the hierarchical structure display table.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a hierarchical structuregenerating method and apparatus for generating and displaying thehierarchical structure of parent and child stations included in a mobilecommunication system or the like, by using a table for indicating eachparent-child relationship of the relevant parent and child stations.

[0003] This application is based on Patent Application No. Hei 10-361607filed in Japan, the contents of which are incorporated herein byreference.

[0004] 2. Description of the Related Art

[0005] There is a conventional hierarchical structure generating methodapplied to mobile communication systems including parent (or base)stations and child (or sub) stations. In this method, the hierarchicalstructure is constructed by searching a parent-child relationship tableincluding a plurality of data indicating each one-to-one parent-childcorrespondence relationship, and determining each parent-childrelationship (starting from a parent station). In this conventionalmethod, in order to search for each child station, the parent-childrelationship table must be searched from the top. In particular, if thenumber N of the stations is large, the number of times of searching theparent-child relationship table (average: N×N/2) is also large; thus,the speed of displaying the hierarchical structure is degraded.

[0006] As for a child station, in order to determine whether a topstation having a level higher than the level of its parent station ispresent, it is necessary to examine each parent station registered inthe parent-child relationship table so as to detect whether the parentstation also functions as a child station with respect to another(parent) station.

[0007] In an example communication system consisting of a parent stationB and N child stations (relay station R or terminal station T), when thewhole hierarchical structure is generated and displayed based on aparent-child relationship table for indicating each parent-childrelationship between the constituent stations, it is necessary toposition only the parent station B at the top of the displayedstructure. However, if the data of the parent-child relationship tableis insufficient, a relay station R may be positioned at the top in thedisplayed structure, that is, some top stations may be displayed inpractice.

[0008] On the other hand, if the hierarchical structure of acommunication system is displayed in a monitoring system of thecommunication system, it is generally necessary to display each stationin the order from the top in turn. If the order is not kept, a systemerror occurs and the hierarchical structure cannot be displayed.Therefore, a process for specifying the top station is also necessarywhen the hierarchical structure is displayed.

SUMMARY OF THE INVENTION

[0009] In consideration of the above circumstances, an objective of thepresent invention is to provide a hierarchical structure generatingmethod and apparatus used in a communication system (for example,consisting of a parent station B and N child stations (relay station Ror terminal station T), by which the whole hierarchical structure can beefficiently generated and displayed from the top level based on aparent-child relationship table between the constituent stations. Morespecifically, the objective is to provide a hierarchical structuregenerating method and apparatus used in such a communication system, bywhich when the hierarchical structure is generated and displayed, it isunnecessary to search the parent-child relationship table every timeeach station is searched for, but each parent-child relationship can bereferred to only by a single search, and a top station other than thecurrent parent station can be detected also by a single search, therebyefficiently generating and displaying the whole hierarchical structurefrom the top level in turn.

[0010] Therefore, the present invention provides a method of generatinga hierarchical structure including a plurality of elements havingparent-child relationships, comprising the steps of:

[0011] referring to a parent-child relationship table indicating eachparent-child relationship between the elements, and generating andoutputting a hierarchical structure display table which includes atleast information for determining whether each element is a parentelement; information for determining whether each parent element is atop parent element; information for determining a child element of eachparent element; and information for determining another child elementhaving the same hierarchical level of each child element, so as toanalyze the hierarchical structure; and

[0012] generating and displaying the hierarchical structure of theelements by referring to the hierarchical structure display table.

[0013] In the above method, the hierarchical structure display table mayconsist of one or more array variables.

[0014] Preferably, the element number, the value, and the sign of thevalue of each element of said one or more array variables are specifiedso as to indicate all of said information.

[0015] Typically, the elements having parent-child relationshipscorrespond to one or more parent stations and N child stations, N beinga natural number, which constitute a communication system.

[0016] The present invention also provides an apparatus for generating ahierarchical structure including a plurality of elements havingparent-child relationships, comprising:

[0017] a hierarchical structure analyzing section for referring to aparent-child relationship table indicating each parent-childrelationship between the elements, and generating and outputting ahierarchical structure display table which includes at least informationfor determining whether each element is a parent element; informationfor determining whether each parent element is a top parent element;information for determining a child element of each parent element; andinformation for determining another child element having the samehierarchical level of each child element, so as to analyze thehierarchical structure; and

[0018] a hierarchical structure display section for generating anddisplaying the hierarchical structure of the elements by referring tothe hierarchical structure display table.

[0019] According to the present invention, the above hierarchicalstructure display table is generated and displayed by referring to aparent-child relationship table, and the hierarchical structure of theconstituent elements, thereby efficiently generating and displaying thehierarchical structure from the top level.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1 is a block diagram showing the structure of thehierarchical structure generating apparatus as an embodiment accordingto the present invention.

[0021]FIG. 2 is an operational flowchart of the hierarchical structureanalyzing section 100 of FIG. 1.

[0022]FIGS. 3A and 3B are operational flowcharts of the hierarchicalstructure display section 200 of FIG. 1.

[0023]FIG. 4A is a diagram showing an example of the parent-childrelationship table 10 in FIG. 1, and FIG. 4B is the hierarchicalstructure corresponding to this example.

[0024]FIG. 5 is a diagram for explaining the operation (performed by thehierarchical structure analyzing section 100 of FIG. 1 along theoperational flow as shown in FIG. 2) of analyzing the hierarchicalstructure, which shows the variation of each variable in the process ofoutputting the hierarchical structure display table 11 according to theparent-child relationship table 10 of FIG. 4.

[0025]FIG. 6 is a diagram for explaining the processes (executed by thehierarchical structure display section 200 of FIG. 1) for displaying thehierarchical structure based on the hierarchical structure display table11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, an embodiment of the present invention will beexplained with reference to the drawings. In the following embodiment,the present invention is applied to a mobile communication system, butthe applicable fields of the present invention are not limited to such asystem, and may include any system having a hierarchical structureincluding parent-child relationships.

[0027]FIG. 1 is a block diagram showing the structure of an embodimentof the hierarchical structure generating apparatus according to thepresent invention.

[0028] In the embodiment shown in FIG. 1, hierarchical structureanalyzing section 100 refers to parent-child relationship table 10storing a plurality of data indicating each parent-child relationshipbetween the stations, so as to generate and output hierarchicalstructure display table 11 which is used as intermediate data fordisplaying the hierarchical structure. The hierarchical structuredisplay section 200 generates and displays the finally fixedhierarchical structure based on the hierarchical structure display table11.

[0029] Typically, each section is realized using a CPU (centralprocessing unit), peripheral devices such as a memory device, andsoftware programs executed using the CPU and the peripheral devices.These constituents are included in a monitoring system for monitoringthe communication system, or one or more parent stations B and N childstations (relay station R and terminal station T) of the system. Here,each table consists of a plurality of data stored in the memory device.In addition, the hierarchical structure analyzing section 100 and thehierarchical structure display section 200 may be separately provided indifferent units, and be connected with each other via a communicationline.

[0030]FIG. 2 is the operational flowchart of the hierarchical structureanalyzing section 100, while FIGS. 3A and 3B are the operationalflowchart of the hierarchical structure display section 200. FIG. 4A isa diagram showing an example of parent-child relationship table 10.

[0031] The parent-child relationship table 10 shown in FIG. 4A includesa plurality of data indicating each parent-child relationship betweenthe stations 1 to 7 which have the hierarchical structure shown in FIG.4B. In the parent-child relationship table 10 of this case, each linecorresponds to each parent-child relationship. The data included in eachline (called each data set) are the first item “No.” indicating the linenumber (which corresponds to variable j in FIG. 5 explained later), thesecond item “HIGHER STATION No.” indicating the parent station of eachparent-child relationship, and the third item “STATION No.” indicatingthe corresponding child station. For example, the first line (lineNo.=1) shows parent-child relationship 41 (see FIG. 4B) in which station1 is the parent station while station 4 is its child station, while thethird line (line No.=3) shows another parent-child relationship 42 (seeFIG. 4B) in which station 4 is the parent station while station 2 is itschild station.

[0032]FIG. 5 is a diagram for explaining the operation (performed by thehierarchical structure analyzing section 100 along the operational flowas shown in FIG. 2) of analyzing the hierarchical structure, which showsthe variation of each variable in the process of outputting thehierarchical structure display table 11 of FIG. 1 according to theparent-child relationship table 10 of FIG. 4.

[0033] In FIG. 5, variable j corresponds to variable j, shown in FIG. 2,which is increased by 1 for each cycle from step 103 to step 112. Thatis, j has one of values 1 to number M (=5) of the data sets of theparent-child relationship table 10 shown in FIG. 4A.

[0034] Array variables R(i) and L(i) (i=1 to N, where N is the number ofthe stations) respectively have initial values 8 and 0. The arrayvariables vary through steps 103 to 112 depending on variable j whosevalue also varies, and these array variables are used for generating thehierarchical structure display table 11.

[0035]FIG. 5 shows the relevant values after each change of the arrayvariables R(i) and L(i). For example, the value of R(1) is changed to −1while j=1, while the value of R(4) is changed to 0 while j=1 and againchanged to 3 while j=3.

[0036] Each element of array R(i), a constituent for generating thehierarchical structure display table 11, has a specific value andpositive or negative sign, thereby indicating the following items:

[0037] (i) whether station i is a parent station, that is, has a childstation connected thereto (in the case of FIG. 5, when R(i) has a valueother than 0 or 8 (initial value), the station i is the parent station),

[0038] (ii) when station i is the parent station, whether the station iis the highest parent station, that is, the top station (in the case ofFIG. 5, when R(i) has a value other than 0 or 8 (initial value) and alsohas the negative sign, the station i is the top station),

[0039] (iii) when station i is the parent station, the absolute value|R(i)|of R(i) indicates that element L(|R(i)|) of array L(i) has a valuecorresponding to the station No. (of a relevant child station) which isstored in the data-set line (of the parent-child relationship table 10)having the smallest line number.

[0040] In the case of FIG. 5, if station i is a child station having nochild station connected thereto, R(i) is set to 0. Additionally, in thepresent embodiment, if data of station i is not included in parent-childrelationship table 10, R(i) keeps the initial value 8 (no such stationis present in the case shown in FIG. 5).

[0041] In the example shown by FIG. 5, R(1), R(4), and R(5) of thehierarchical structure display table 11 respectively have values −1, 3,and −4; thus, as shown in FIG. 4B, stations 1, 4, and 5 are parentstations, and the stations 1 and 5 are the top stations. In addition,the station No. 4 of the first child station of station 1 is stored invariable L(1) (here, the stored value having the negative sign), thestation No. 2 of the first child station of station 4 is stored invariable L(3) (here, the stored value also having the negative sign),and the station No. 3 of the first child station of station 5 is storedin variable L(4) (here, the stored value also having the negative sign).

[0042] The remaining elements R(2), R(3), R(6), and R(7) have value 0,thereby indicating that stations 2, 3, 6, and 7 are child stationsincluded in the hierarchical structure.

[0043] On the other hand, each element of array variable L(i), anotherconstituent for generating the hierarchical structure display table 11,has the element number equal to the corresponding data-set (i.e., line)No., where the element corresponds to the station No. of the relevantchild station included in the parent-child relationship table 10, andhas the absolute value (i.e., integer) of the corresponding station No.,to which a positive or negative sign is appended. The positive ornegative sign indicates that whether another child station connected tothe parent station of the relevant child station is present, that is,whether another child station having the same hierarchical level ispresent.

[0044] In the example as shown by FIG. 5, each element of array L(i) hasthe absolute value equal to the station No. of the child station in theith data set in the parent-child relationship table 10. If another childstation having the same hierarchical level is present in the (i−1)thdata set of the hierarchical structure display table 10, the absolutevalue has a positive sign (refer to L(2) and L(5)), or else (that is, nosuch child station exists) the absolute value has a negative sign (referto L(1), L(3) and L(4)). If no data set corresponding to i is present inthe parent-child relationship table 10, the element has and keeps itsinitial value 0 (refer to L(6) and L(7) of FIG. 5).

[0045] The method of setting values assigned to the elements of eacharray for generating the hierarchical structure display table 11 is notlimited to the above case, but any modification is possible, forexample, the initial values may be changed, or the positive and negativesigns may be reversed.

[0046] The operations of each structural element of FIG. 1 of thepresent embodiment will be explained below.

[0047] (1) Operation of hierarchical structure analyzing section 100

[0048] Based on the flowchart of FIG. 2, the operation will be explainedusing FIGS. 4 and 5. Here, it is assumed that data of the parent-childrelationship table 10 of FIG. 4 is sorted in advance in the order of thehigher station No. (from the smallest to the largest), and that noduplicate station No. is used.

[0049] First, variables R(i) (i=1 to N) and L(i) (i=0 to N) in thehierarchical structure display table 10 are initialized (see step 101).Here, N is the number of stations, and value N+1 is substituted (orinput) into R(i) while value 0 is substituted into L(i).

[0050] Next, work variable “iu” (used for storing the higher stationNo.) is initialized, that is, N+1 is given to variable iu (see step102). Next, the processes from step 103 to step 112 are repeated fromj=1 to M (M is the number of data items (i.e., the number of lines) ofthe parent-child relationship table 10).

[0051] In step 104, the jth data of the parent-child relationship tableis referred to, and the relevant station No. is substituted intovariable k while the relevant higher station No. is substituted intovariable i. In the next step 105, variables k and i are compared, and ifthey equal each other, the operation jumps to step 111, or else theoperation proceeds to the next step 106. In step 106, variables i and iuare compared, and if they are not equal to each other, the operationproceeds to step 107 a, or else the operation jumps to step 109.

[0052] In step 107 a, the value of variable R(i) is checked, and ifR(i)=0, then +j is substituted into R(i) (see step 107 b), or ifR(i)=N+1, then −j is substituted into R(i) (see step 107 c). In the nextstep 108, −k is substituted into L(j), and the operation proceeds tostep 110 a. On the other hand, in step 109, +k is substituted into L(j),and the operation proceeds to step 110 a.

[0053] In step 110 a, the value of variable R(k) is checked, and ifR(k)=N+1, then 0 is substituted into R(k) (see step 110 b), or ifR(k)<0, then the absolute value of R(k) is substituted into R(k) (seestep 110 c). In the next step 111, the value of variable i issubstituted into variable iu (that is, the higher station No. is savedin variable iu).

[0054] In the above way, the hierarchical structure analyzing section200 uses input data from the parent-child relationship table shown inFIG. 4 and changes variable j from 1 to M (=5), and sets variables R(i)and L(i) (as shown in FIG. 5) while executing steps 104 to 111, andlastly generates and outputs the hierarchical structure display table 11of FIG. 5.

[0055] In FIG. 2, in the process 107 consisting of steps 107 a to 107 c,if the current higher station (having the higher station No. i) wasalready processed as a lower station in an earlier process (related tostep 110 b), the positive value of j (the array element number ofvariable L(j) which stores the station No. (−k) of the relevant childstation) is substituted into variable R(i) (see step 107 b). While ifthe current higher station has not yet been processed (that is, theinitial value is still kept), the negative value of j, the elementnumber of variable L(j), is substituted into variable R(i) so as todetermine the current higher station as the top parent station (see step107 c).

[0056] In the process 110 consisting of steps 110 a to 110 c, if thecurrent station having station No. k has not yet been processed yet,variable R(k) is set to 0 so as to indicate that this station is not aparent station but a child station (see step 110 b), or if a value otherthan the initial value has already been given as the top parent station(see step 107 c), the value of variable R(k) is changed to a positivevalue which indicates a parent station but not the top parent station(see step 110 c).

[0057] (2) Operation of Hierarchical Structure Display Section 200

[0058] Referring to the flowcharts of FIGS. 3A and 3B, the operation ofthe hierarchical structure display section 200 will be explained usingFIG. 6. FIG. 6 is a diagram for explaining the processes (performed bythe hierarchical structure display section 200) for displaying thehierarchical structure based on the hierarchical structure display table11.

[0059] In the main routine (i.e., steps 201 to 204) of FIG. 3A, thehierarchical structure display section 200 of FIG. 1 changes variable qfrom 1 to N and simultaneously checks R(q) (see step 202) whilereferring to the hierarchical structure display table 11, and repeatsthe processes firm steps 201 to 204. In the repetition, if R(q) has anegative value, the hierarchical structure display section 200 callsfunction Tree(q, q).

[0060] In function Tree (p, q) (see FIG. 3B), variables p and q arecompared (see step 301 a), and if p=q, then variable q is displayed asthe top station (see step 301 b), while if p≠q, then variable q isdisplayed as a lower station of the station indicated by variable p (seestep 301 c). The steps 301 a to 301 c constitute process 301 fordisplaying the hierarchical structure.

[0061] In the next step 302, the value of variable q is substituted intovariable j, and the absolute value of array variable R(j) of thehierarchical structure display table 11 is substituted into variable i.In step 303, the absolute value of array variable L(i) of thehierarchical structure display table 11 is substituted into variable k.The value of variable k is then checked (see step 304 a), and if k=0,then the operation jumps to step 305, while if k≠0, then function Tree(j, k) is recursively called and executed using arguments j and k (seestep 304 b). Here, in the process 304 consisting of steps 304 a to 304c, if k (i.e., variable L(i)) is not 0, that is, if a lower station tobe further called is present in the same level of the hierarchicalstructure, then function Tree is called.

[0062] In step 305, variable i is increased by 1, and if the conditionsthat variable k>0 and variable L(i)>0 are satisfied in step 306, thenthe operation returns to step 303 and the process of calling functionTree (of step 304) is again executed for the same variable j (that is,with respect to another child station connected to the same parentstation).

[0063] In this way, the hierarchical structure display section 200efficiently generates and displays the hierarchical structure shown inFIG. 4B by using the hierarchical structure display table 11 (of FIG. 5)according to the processes as shown in FIG. 6, that is, along a simplepath without searching the hierarchical structure display table 11 fromthe top.

[0064] Below, the diagram of FIG. 6 for indicating the processes ofdisplaying the hierarchical structure will be explained in detail. FIG.6 shows each process for displaying the hierarchical structure as shownin FIG. 4B with reference to the hierarchical structure display table 11of FIG. 5.

[0065] In the flowcharts of FIGS. 3A and 3B, first, when variable q=1,function Tree (1, 1) is called and the station No. 1 is displayed as thetop station (see reference numeral 601 in FIG. 6). Next, variable R(1)is referred to, and the function Tree (1, 4) is executed using argumentk which is the absolute value of “L(1)=−4” based on variable R(1) (seereference numerals 602 and 603), thereby displaying the station No. 4 asa lower station of the station No. 1.

[0066] Next, variable R(4) is referred to, and the function Tree (4, 2)is executed using argument k which is the absolute value of “L(3)=−2”(see reference numerals 604 and 605), thereby displaying the station No.2 as a lower station of the station No. 4.

[0067] In function Tree (4, 2), variable R(2)=0=i; thus, variableL(0)=0=k, and the execution of function Tree (4, 2) is finished (seereference numeral 606). Next, function Tree (1, 7) is called using adifferent argument which is the absolute value (7) of L(1+1)=L(2) (theprevious argument is the absolute value (4) of L(1)) (see referencenumerals 607 and 608), thereby displaying the station No. 7 as a lowerstation of the station No. 1. Here, R(7)=0; thus, k=0 and the executionof function Tree (1, 7) is finished (see reference numeral 609). Inaddition, L(2+1)=L(3)=−2 (see reference numeral 610), thus the executionof function Tree (1, 1) is finished (see reference numeral 611).

[0068] Next, function Tree (5, 5) is called and executed in step 203 ofthe main routine, and the station No. 5 is displayed as the top station(see reference numeral 612). Next, variable R(5) is referred to, andfunction Tree (5, 3) is executed with argument k which is the absolutevalue of L(4)=−3 (see reference numerals 613 and 614), therebydisplaying the station No. 3 as a lower station of the station No. 5.

[0069] In the execution of function Tree (5, 3), variable R(3)=0; thus,variable L(0)=k=0 and the execution of function Tree (5, 3) is finished(see reference numeral 615). Next, function Tree (5, 6) is called usinga different argument which is the absolute value (6) of L(4+1)=L(5) (theprevious argument is the absolute value (3) of L(4)) (see referencenumerals 616 and 617), thereby displaying the station No. 6 as a lowerstation of the station No. 5. Here, R(6)=0; thus, k=0 and the executionof function Tree (5, 6) is finished (see reference numeral 618). Inaddition, L(5+1)=L(6)=0 (see reference numeral 619); thus, the executionof function Tree (5, 5) is finished (see reference numeral 620).

[0070] In the above way, the hierarchical structure as shown in FIG. 4Bis displayed.

[0071] The present invention is not limited to the above embodiment. Forexample, even if the parent-child relationship data related to stationsNo. 1 to N has a blank, the hierarchical structure of the stationshaving necessary information can be generated and displayed.

[0072] In the above embodiment, the hierarchical structure display table11 consists of array variables R and L, that is, having two variablenames; however, the structure of the hierarchical structure displaytable 11 is not limited to this form. For example, the array variable Rmay be divided into two array variables R1 and R2 and the array variableL may be divided into two array variables L1 and L2, where the variablesR1 and L1 have information on the absolute values of variables R and L,and variables R2 and L2 have information on the (positive or negative)signs of variables R and L. In this case, a similar hierarchicalstructure display table can be constructed using the array variableshaving four variable names. As another example for obtaining a similarhierarchical structure display table, the hierarchical structure displaytable 11 may be constructed using a single array variable, where (i) theodd element numbers are assigned to array variable R and the evenelement numbers are assigned to array variable L, or (ii) apredetermined offset value is defined for realizing a function similarto that using the array variables R and L, by adding or not adding theoffset value.

What is claimed is:
 1. A method of generating a hierarchical structureincluding a plurality of elements having parent-child relationships,comprising the steps of: referring to a parent-child relationship tableindicating each parent-child relationship between the elements, andgenerating and outputting a hierarchical structure display table whichincludes at least information for determining whether each element is aparent element; information for determining whether each parent elementis a top parent element; information for determining a child element ofeach parent element; and information for determining another childelement having the same hierarchical level of each child element, so asto analyze the hierarchical structure; and generating and displaying thehierarchical structure of the elements by referring to the hierarchicalstructure display table.
 2. A method as claimed in claim 1, wherein thehierarchical structure display table consists of one or more arrayvariables.
 3. A method as claimed in claim 1, wherein the elementnumber, the value, and the sign of the value of each element of said oneor more array variables are specified so as to indicate all of saidinformation.
 4. A method as claimed in claim 2, wherein the elementnumber, the value, and the sign of the value of each element of said oneor more array variables are specified so as to indicate all of saidinformation.
 5. A method as claimed in claim 1, wherein the elementshaving parent-child relationships correspond to one or more parentstations and N child stations, N being a natural number, whichconstitute a communication system.
 6. An apparatus of generating ahierarchical structure including a plurality of elements havingparent-child relationships, comprising: a hierarchical structureanalyzing section for referring to a parent-child relationship tableindicating each parent-child relationship between the elements, andgenerating and outputting a hierarchical structure display table whichincludes at least information for determining whether each element is aparent element; information for determining whether each parent elementis a top parent element; information for determining a child element ofeach parent element; and information for determining another childelement having the same hierarchical level of each child element, so asto analyze the hierarchical structure; and a hierarchical structuredisplay section for generating and displaying the hierarchical structureof the elements by referring to the hierarchical structure displaytable.